Mobile computing continues to grow quickly as mobile devices, such as smart phones, add more power and more features. Users of such devices may now access various services on the Internet, such as mapping applications, electronic mail, text messaging, various telephone services, general web browsing, music and video viewing, and other such services. Mobile devices can take forms such as smart phones, tablets and netbooks.
Mobile devices frequently obtain network access wirelessly. While certain access may occur via private data networks run by telecommunication providers, such as 3G networks, that access may carry with it a relatively high monthly or per minute fee. Mobile devices may also communicate wirelessly through standard WiFi access points. Such access points may be made available for free or for a charge in locations where computer users are likely to congregate momentarily, such as airport terminals, coffees shops, and buildings on university campuses. A mobile device may be set up in such a situation to scan for access points for which a beacon signal is available, and may report to a user on a screen of their device the names of networks that are within the wireless vicinity of the mobile device. Scanning can involve tuning a wireless interface to detect wireless signals broadcast at various frequencies (e.g., 2.4 GHz, 5 GHz), on various channels (e.g., channels 1-11), and using various wireless standards (e.g., 802.11g, 802.11n, 3G, 4G). Such scanning, if performed constantly, can quickly run down the batteries on a mobile device.